The Madness of Hercules takes up the story with Jason (Jack Donnelly) imprisoned, accused of the murder of the Oracle (despite her having been turned to stone – something Jason is clearly not capable of). Half the airtime is spent with much hand-wringing over Queen Ariadne (Aiysha Hart) not being able to defy Poseidon and Hercules (Mark Addy) unable to ask his beloved Medusa (Jemima Rooper) to confess to the murder. Medusa is now no longer a gorgon, but almost unable to live with her actions.

Action continues with a solid, but failed, rescue before Jason and Hercules escape the city. Before the view can even say ‘just who, exactly, are some of these new characters suddenly getting so much air-time’ than Ariadne is accused of blasphemy and herself condemned to die. As soon as Pythagoras (Robert Emms) gets the message out, Jason, Hercules and Medusa then make their way back into Atlantis. It all seems too late, Pasiphae (Sarah Parish) is now in charge.

This is a very frustrating piece of entertainment in that it haphazardly shuffles pieces around with the apparent intention of setting up a grand climax in a later story. At no point do we understand how the ordinary inhabitants of the city (if there are any) deal with Jason moving from here to villain every other week, the Queen going from beloved monarch to evil blasphemy and so forth. While there are many nice touches (Addy and Rooper’s love story between Hercules and Medusa has been brilliant) the story feels a little like an episode of The Simpsons - the one where Bart explains to Crusty how many times he has saved his life and/or career, leading Crusty to ask what Bart had done for him recently. Atlantis is not the Simpsons and without some measure of stability (yes betrayals and dark secrets make good drama) the show has no compass and under-achieves.

At least the clips from next week’s The Gorgon’s Gaze promise some more powerful television with suggestions that Medusa’s cure may not be very permanent.

Overall then, this is merely setting the scene for what needs to be a more impressive conclusion to this arc.